Throughout history, rodents such as mice and rats have been persistent pests, consuming food supplies, soiling human habitations and workplaces, and spreading contaminants and disease. Rodents may be killed by the placement of poison in a form attractive to the rodent. However, in certain applications poisoned bait may be ineffective, for example in a granary where attractive rodent food is omnipresent. In other applications, poison may be unacceptable because of the close proximity to human food or non-target species, including pets.
Mechanical traps which use stored kinetic energy to enclose or crush the rodent have the advantage of retaining the dead rodent at a specific site for disposal. However, the moving parts of a mechanical trap add to the cost of manufacture.
Adhesive devices have been developed which present an expanse of highly retentive glue along a path frequented by rodents. A rodent making contact with the adhesive will be held and prevented from departure. Eventually the rodent will become suffocated in the adhesive, or will otherwise die. The glue-containing board and dead rodent may then be disposed of as a single unit.
Convenient packaging and shipment of glue boards is of great concern. The adhesive nature of such devices means that they must be shielded from contact with dirt and debris prior to use, lest the adhesive properties be reduced. Furthermore, for convenience to the user, the adhesive should be shielded from contact with clothing, hands, furniture, etc., until ready to be placed along a rodent runway.
Prior art glue boards have employed thermoformed plastic trays to contain the adhesive, and these trays have had indented portions with a flange which extends around the tray above the surface of the entrapping glue. Thus two prior art glue boards may be placed flange to flange, thereby spacing the glue of each from adhesive contact. Glue boards in the form of filled trays are advantageous from a manufacturing standpoint because of the simplicity of assembling two trays into a single saleable unit, and for the convenience of separating two snap-connected trays in the field.
Rodent glue boards filled with a hotmelt adhesive have been developed for shipment nationwide. Shipment by truck and storage of the packaged glue traps will subject the adhesive to elevated temperatures, and conventional glue traps have had to address the possibility of an inverted trap losing its glue as the adhesive becomes more flowable at higher temperatures. Commonly, flowing of the glue has been lessened by the use of a glue which is more resistant to flow at expected temperatures. Unfortunately, this change almost always comes at the cost of glue tackiness and rodent entrapping strength.
What is needed is an adhesive control device for rodents which allows compact and convenient packaging, which supports ready rodent entrapment, and which is fully transportable.